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Diffstat (limited to 'js/src/wasm/WasmCode.cpp')
| -rw-r--r-- | js/src/wasm/WasmCode.cpp | 1253 |
1 files changed, 1253 insertions, 0 deletions
diff --git a/js/src/wasm/WasmCode.cpp b/js/src/wasm/WasmCode.cpp new file mode 100644 index 0000000000..063d2a020c --- /dev/null +++ b/js/src/wasm/WasmCode.cpp @@ -0,0 +1,1253 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * vim: set ts=8 sts=2 et sw=2 tw=80: + * + * Copyright 2016 Mozilla Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "wasm/WasmCode.h" + +#include "mozilla/Atomics.h" +#include "mozilla/BinarySearch.h" +#include "mozilla/EnumeratedRange.h" +#include "mozilla/Sprintf.h" + +#include <algorithm> + +#include "jsnum.h" + +#include "jit/Disassemble.h" +#include "jit/ExecutableAllocator.h" +#include "jit/MacroAssembler.h" +#include "jit/PerfSpewer.h" +#include "util/Poison.h" +#ifdef MOZ_VTUNE +# include "vtune/VTuneWrapper.h" +#endif +#include "wasm/WasmModule.h" +#include "wasm/WasmProcess.h" +#include "wasm/WasmSerialize.h" +#include "wasm/WasmStubs.h" +#include "wasm/WasmUtility.h" + +using namespace js; +using namespace js::jit; +using namespace js::wasm; +using mozilla::BinarySearch; +using mozilla::BinarySearchIf; +using mozilla::MakeEnumeratedRange; +using mozilla::PodAssign; + +size_t LinkData::SymbolicLinkArray::sizeOfExcludingThis( + MallocSizeOf mallocSizeOf) const { + size_t size = 0; + for (const Uint32Vector& offsets : *this) { + size += offsets.sizeOfExcludingThis(mallocSizeOf); + } + return size; +} + +CodeSegment::~CodeSegment() { + if (unregisterOnDestroy_) { + UnregisterCodeSegment(this); + } +} + +static uint32_t RoundupCodeLength(uint32_t codeLength) { + // AllocateExecutableMemory() requires a multiple of ExecutableCodePageSize. + return RoundUp(codeLength, ExecutableCodePageSize); +} + +UniqueCodeBytes wasm::AllocateCodeBytes(uint32_t codeLength) { + if (codeLength > MaxCodeBytesPerProcess) { + return nullptr; + } + + static_assert(MaxCodeBytesPerProcess <= INT32_MAX, "rounding won't overflow"); + uint32_t roundedCodeLength = RoundupCodeLength(codeLength); + + void* p = + AllocateExecutableMemory(roundedCodeLength, ProtectionSetting::Writable, + MemCheckKind::MakeUndefined); + + // If the allocation failed and the embedding gives us a last-ditch attempt + // to purge all memory (which, in gecko, does a purging GC/CC/GC), do that + // then retry the allocation. + if (!p) { + if (OnLargeAllocationFailure) { + OnLargeAllocationFailure(); + p = AllocateExecutableMemory(roundedCodeLength, + ProtectionSetting::Writable, + MemCheckKind::MakeUndefined); + } + } + + if (!p) { + return nullptr; + } + + // Zero the padding. + memset(((uint8_t*)p) + codeLength, 0, roundedCodeLength - codeLength); + + // We account for the bytes allocated in WasmModuleObject::create, where we + // have the necessary JSContext. + + return UniqueCodeBytes((uint8_t*)p, FreeCode(roundedCodeLength)); +} + +bool CodeSegment::initialize(const CodeTier& codeTier) { + MOZ_ASSERT(!initialized()); + codeTier_ = &codeTier; + MOZ_ASSERT(initialized()); + + // In the case of tiering, RegisterCodeSegment() immediately makes this code + // segment live to access from other threads executing the containing + // module. So only call once the CodeSegment is fully initialized. + if (!RegisterCodeSegment(this)) { + return false; + } + + // This bool is only used by the destructor which cannot be called racily + // and so it is not a problem to mutate it after RegisterCodeSegment(). + MOZ_ASSERT(!unregisterOnDestroy_); + unregisterOnDestroy_ = true; + return true; +} + +const Code& CodeSegment::code() const { + MOZ_ASSERT(codeTier_); + return codeTier_->code(); +} + +void CodeSegment::addSizeOfMisc(MallocSizeOf mallocSizeOf, size_t* code) const { + *code += RoundupCodeLength(length()); +} + +void FreeCode::operator()(uint8_t* bytes) { + MOZ_ASSERT(codeLength); + MOZ_ASSERT(codeLength == RoundupCodeLength(codeLength)); + +#ifdef MOZ_VTUNE + vtune::UnmarkBytes(bytes, codeLength); +#endif + DeallocateExecutableMemory(bytes, codeLength); +} + +bool wasm::StaticallyLink(const ModuleSegment& ms, const LinkData& linkData) { + for (LinkData::InternalLink link : linkData.internalLinks) { + CodeLabel label; + label.patchAt()->bind(link.patchAtOffset); + label.target()->bind(link.targetOffset); +#ifdef JS_CODELABEL_LINKMODE + label.setLinkMode(static_cast<CodeLabel::LinkMode>(link.mode)); +#endif + Assembler::Bind(ms.base(), label); + } + + if (!EnsureBuiltinThunksInitialized()) { + return false; + } + + for (auto imm : MakeEnumeratedRange(SymbolicAddress::Limit)) { + const Uint32Vector& offsets = linkData.symbolicLinks[imm]; + if (offsets.empty()) { + continue; + } + + void* target = SymbolicAddressTarget(imm); + for (uint32_t offset : offsets) { + uint8_t* patchAt = ms.base() + offset; + Assembler::PatchDataWithValueCheck(CodeLocationLabel(patchAt), + PatchedImmPtr(target), + PatchedImmPtr((void*)-1)); + } + } + + return true; +} + +void wasm::StaticallyUnlink(uint8_t* base, const LinkData& linkData) { + for (LinkData::InternalLink link : linkData.internalLinks) { + CodeLabel label; + label.patchAt()->bind(link.patchAtOffset); + label.target()->bind(-size_t(base)); // to reset immediate to null +#ifdef JS_CODELABEL_LINKMODE + label.setLinkMode(static_cast<CodeLabel::LinkMode>(link.mode)); +#endif + Assembler::Bind(base, label); + } + + for (auto imm : MakeEnumeratedRange(SymbolicAddress::Limit)) { + const Uint32Vector& offsets = linkData.symbolicLinks[imm]; + if (offsets.empty()) { + continue; + } + + void* target = SymbolicAddressTarget(imm); + for (uint32_t offset : offsets) { + uint8_t* patchAt = base + offset; + Assembler::PatchDataWithValueCheck(CodeLocationLabel(patchAt), + PatchedImmPtr((void*)-1), + PatchedImmPtr(target)); + } + } +} + +static bool AppendToString(const char* str, UTF8Bytes* bytes) { + return bytes->append(str, strlen(str)) && bytes->append('\0'); +} + +static void SendCodeRangesToProfiler(const ModuleSegment& ms, + const Metadata& metadata, + const CodeRangeVector& codeRanges) { + bool enabled = false; + enabled |= PerfEnabled(); +#ifdef MOZ_VTUNE + enabled |= vtune::IsProfilingActive(); +#endif + if (!enabled) { + return; + } + + for (const CodeRange& codeRange : codeRanges) { + if (!codeRange.hasFuncIndex()) { + continue; + } + + uintptr_t start = uintptr_t(ms.base() + codeRange.begin()); + uintptr_t size = codeRange.end() - codeRange.begin(); + + UTF8Bytes name; + if (!metadata.getFuncNameStandalone(codeRange.funcIndex(), &name)) { + return; + } + + // Avoid "unused" warnings + (void)start; + (void)size; + + if (PerfEnabled()) { + const char* file = metadata.filename.get(); + if (codeRange.isFunction()) { + if (!name.append('\0')) { + return; + } + unsigned line = codeRange.funcLineOrBytecode(); + CollectPerfSpewerWasmFunctionMap(start, size, file, line, name.begin()); + } else if (codeRange.isInterpEntry()) { + if (!AppendToString(" slow entry", &name)) { + return; + } + CollectPerfSpewerWasmMap(start, size, file, name.begin()); + } else if (codeRange.isJitEntry()) { + if (!AppendToString(" fast entry", &name)) { + return; + } + CollectPerfSpewerWasmMap(start, size, file, name.begin()); + } else if (codeRange.isImportInterpExit()) { + if (!AppendToString(" slow exit", &name)) { + return; + } + CollectPerfSpewerWasmMap(start, size, file, name.begin()); + } else if (codeRange.isImportJitExit()) { + if (!AppendToString(" fast exit", &name)) { + return; + } + CollectPerfSpewerWasmMap(start, size, file, name.begin()); + } else { + MOZ_CRASH("unhandled perf hasFuncIndex type"); + } + } +#ifdef MOZ_VTUNE + if (!vtune::IsProfilingActive()) { + continue; + } + if (!codeRange.isFunction()) { + continue; + } + if (!name.append('\0')) { + return; + } + vtune::MarkWasm(vtune::GenerateUniqueMethodID(), name.begin(), (void*)start, + size); +#endif + } +} + +ModuleSegment::ModuleSegment(Tier tier, UniqueCodeBytes codeBytes, + uint32_t codeLength, const LinkData& linkData) + : CodeSegment(std::move(codeBytes), codeLength, CodeSegment::Kind::Module), + tier_(tier), + trapCode_(base() + linkData.trapOffset) {} + +/* static */ +UniqueModuleSegment ModuleSegment::create(Tier tier, MacroAssembler& masm, + const LinkData& linkData) { + uint32_t codeLength = masm.bytesNeeded(); + + UniqueCodeBytes codeBytes = AllocateCodeBytes(codeLength); + if (!codeBytes) { + return nullptr; + } + + masm.executableCopy(codeBytes.get()); + + return js::MakeUnique<ModuleSegment>(tier, std::move(codeBytes), codeLength, + linkData); +} + +/* static */ +UniqueModuleSegment ModuleSegment::create(Tier tier, const Bytes& unlinkedBytes, + const LinkData& linkData) { + uint32_t codeLength = unlinkedBytes.length(); + + UniqueCodeBytes codeBytes = AllocateCodeBytes(codeLength); + if (!codeBytes) { + return nullptr; + } + + memcpy(codeBytes.get(), unlinkedBytes.begin(), codeLength); + + return js::MakeUnique<ModuleSegment>(tier, std::move(codeBytes), codeLength, + linkData); +} + +bool ModuleSegment::initialize(const CodeTier& codeTier, + const LinkData& linkData, + const Metadata& metadata, + const MetadataTier& metadataTier) { + if (!StaticallyLink(*this, linkData)) { + return false; + } + + // Optimized compilation finishes on a background thread, so we must make sure + // to flush the icaches of all the executing threads. + // Reprotect the whole region to avoid having separate RW and RX mappings. + if (!ExecutableAllocator::makeExecutableAndFlushICache( + base(), RoundupCodeLength(length()))) { + return false; + } + + SendCodeRangesToProfiler(*this, metadata, metadataTier.codeRanges); + + // See comments in CodeSegment::initialize() for why this must be last. + return CodeSegment::initialize(codeTier); +} + +void ModuleSegment::addSizeOfMisc(mozilla::MallocSizeOf mallocSizeOf, + size_t* code, size_t* data) const { + CodeSegment::addSizeOfMisc(mallocSizeOf, code); + *data += mallocSizeOf(this); +} + +const CodeRange* ModuleSegment::lookupRange(const void* pc) const { + return codeTier().lookupRange(pc); +} + +size_t CacheableChars::sizeOfExcludingThis(MallocSizeOf mallocSizeOf) const { + return mallocSizeOf(get()); +} + +size_t MetadataTier::sizeOfExcludingThis(MallocSizeOf mallocSizeOf) const { + return funcToCodeRange.sizeOfExcludingThis(mallocSizeOf) + + codeRanges.sizeOfExcludingThis(mallocSizeOf) + + callSites.sizeOfExcludingThis(mallocSizeOf) + + tryNotes.sizeOfExcludingThis(mallocSizeOf) + + trapSites.sizeOfExcludingThis(mallocSizeOf) + + funcImports.sizeOfExcludingThis(mallocSizeOf) + + funcExports.sizeOfExcludingThis(mallocSizeOf); +} + +UniqueLazyStubSegment LazyStubSegment::create(const CodeTier& codeTier, + size_t length) { + UniqueCodeBytes codeBytes = AllocateCodeBytes(length); + if (!codeBytes) { + return nullptr; + } + + auto segment = js::MakeUnique<LazyStubSegment>(std::move(codeBytes), length); + if (!segment || !segment->initialize(codeTier)) { + return nullptr; + } + + return segment; +} + +bool LazyStubSegment::hasSpace(size_t bytes) const { + MOZ_ASSERT(AlignBytesNeeded(bytes) == bytes); + return bytes <= length() && usedBytes_ <= length() - bytes; +} + +bool LazyStubSegment::addStubs(const Metadata& metadata, size_t codeLength, + const Uint32Vector& funcExportIndices, + const FuncExportVector& funcExports, + const CodeRangeVector& codeRanges, + uint8_t** codePtr, + size_t* indexFirstInsertedCodeRange) { + MOZ_ASSERT(hasSpace(codeLength)); + + size_t offsetInSegment = usedBytes_; + *codePtr = base() + usedBytes_; + usedBytes_ += codeLength; + + *indexFirstInsertedCodeRange = codeRanges_.length(); + + if (!codeRanges_.reserve(codeRanges_.length() + 2 * codeRanges.length())) { + return false; + } + + size_t i = 0; + for (uint32_t funcExportIndex : funcExportIndices) { + const FuncExport& fe = funcExports[funcExportIndex]; + const FuncType& funcType = metadata.getFuncExportType(fe); + const CodeRange& interpRange = codeRanges[i]; + MOZ_ASSERT(interpRange.isInterpEntry()); + MOZ_ASSERT(interpRange.funcIndex() == + funcExports[funcExportIndex].funcIndex()); + + codeRanges_.infallibleAppend(interpRange); + codeRanges_.back().offsetBy(offsetInSegment); + i++; + + if (!funcType.canHaveJitEntry()) { + continue; + } + + const CodeRange& jitRange = codeRanges[i]; + MOZ_ASSERT(jitRange.isJitEntry()); + MOZ_ASSERT(jitRange.funcIndex() == interpRange.funcIndex()); + + codeRanges_.infallibleAppend(jitRange); + codeRanges_.back().offsetBy(offsetInSegment); + i++; + } + + return true; +} + +const CodeRange* LazyStubSegment::lookupRange(const void* pc) const { + // Do not search if the search will not find anything. There can be many + // segments, each with many entries. + if (pc < base() || pc >= base() + length()) { + return nullptr; + } + return LookupInSorted(codeRanges_, + CodeRange::OffsetInCode((uint8_t*)pc - base())); +} + +void LazyStubSegment::addSizeOfMisc(MallocSizeOf mallocSizeOf, size_t* code, + size_t* data) const { + CodeSegment::addSizeOfMisc(mallocSizeOf, code); + *data += codeRanges_.sizeOfExcludingThis(mallocSizeOf); + *data += mallocSizeOf(this); +} + +// When allocating a single stub to a page, we should not always place the stub +// at the beginning of the page as the stubs will tend to thrash the icache by +// creating conflicts (everything ends up in the same cache set). Instead, +// locate stubs at different line offsets up to 3/4 the system page size (the +// code allocation quantum). +// +// This may be called on background threads, hence the atomic. + +static void PadCodeForSingleStub(MacroAssembler& masm) { + // Assume 64B icache line size + static uint8_t zeroes[64]; + + // The counter serves only to spread the code out, it has no other meaning and + // can wrap around. + static mozilla::Atomic<uint32_t, mozilla::MemoryOrdering::ReleaseAcquire> + counter(0); + + uint32_t maxPadLines = ((gc::SystemPageSize() * 3) / 4) / sizeof(zeroes); + uint32_t padLines = counter++ % maxPadLines; + for (uint32_t i = 0; i < padLines; i++) { + masm.appendRawCode(zeroes, sizeof(zeroes)); + } +} + +static constexpr unsigned LAZY_STUB_LIFO_DEFAULT_CHUNK_SIZE = 8 * 1024; + +bool LazyStubTier::createManyEntryStubs(const Uint32Vector& funcExportIndices, + const Metadata& metadata, + const CodeTier& codeTier, + size_t* stubSegmentIndex) { + MOZ_ASSERT(funcExportIndices.length()); + + LifoAlloc lifo(LAZY_STUB_LIFO_DEFAULT_CHUNK_SIZE); + TempAllocator alloc(&lifo); + JitContext jitContext; + WasmMacroAssembler masm(alloc); + + if (funcExportIndices.length() == 1) { + PadCodeForSingleStub(masm); + } + + const MetadataTier& metadataTier = codeTier.metadata(); + const FuncExportVector& funcExports = metadataTier.funcExports; + uint8_t* moduleSegmentBase = codeTier.segment().base(); + + CodeRangeVector codeRanges; + DebugOnly<uint32_t> numExpectedRanges = 0; + for (uint32_t funcExportIndex : funcExportIndices) { + const FuncExport& fe = funcExports[funcExportIndex]; + const FuncType& funcType = metadata.getFuncExportType(fe); + // Exports that don't support a jit entry get only the interp entry. + numExpectedRanges += (funcType.canHaveJitEntry() ? 2 : 1); + void* calleePtr = + moduleSegmentBase + metadataTier.codeRange(fe).funcUncheckedCallEntry(); + Maybe<ImmPtr> callee; + callee.emplace(calleePtr, ImmPtr::NoCheckToken()); + if (!GenerateEntryStubs(masm, funcExportIndex, fe, funcType, callee, + /* asmjs */ false, &codeRanges)) { + return false; + } + } + MOZ_ASSERT(codeRanges.length() == numExpectedRanges, + "incorrect number of entries per function"); + + masm.finish(); + + MOZ_ASSERT(masm.callSites().empty()); + MOZ_ASSERT(masm.callSiteTargets().empty()); + MOZ_ASSERT(masm.trapSites().empty()); + MOZ_ASSERT(masm.tryNotes().empty()); + + if (masm.oom()) { + return false; + } + + size_t codeLength = LazyStubSegment::AlignBytesNeeded(masm.bytesNeeded()); + + if (!stubSegments_.length() || + !stubSegments_[lastStubSegmentIndex_]->hasSpace(codeLength)) { + size_t newSegmentSize = std::max(codeLength, ExecutableCodePageSize); + UniqueLazyStubSegment newSegment = + LazyStubSegment::create(codeTier, newSegmentSize); + if (!newSegment) { + return false; + } + lastStubSegmentIndex_ = stubSegments_.length(); + if (!stubSegments_.emplaceBack(std::move(newSegment))) { + return false; + } + } + + LazyStubSegment* segment = stubSegments_[lastStubSegmentIndex_].get(); + *stubSegmentIndex = lastStubSegmentIndex_; + + size_t interpRangeIndex; + uint8_t* codePtr = nullptr; + if (!segment->addStubs(metadata, codeLength, funcExportIndices, funcExports, + codeRanges, &codePtr, &interpRangeIndex)) { + return false; + } + + masm.executableCopy(codePtr); + PatchDebugSymbolicAccesses(codePtr, masm); + memset(codePtr + masm.bytesNeeded(), 0, codeLength - masm.bytesNeeded()); + + for (const CodeLabel& label : masm.codeLabels()) { + Assembler::Bind(codePtr, label); + } + + if (!ExecutableAllocator::makeExecutableAndFlushICache(codePtr, codeLength)) { + return false; + } + + // Create lazy function exports for funcIndex -> entry lookup. + if (!exports_.reserve(exports_.length() + funcExportIndices.length())) { + return false; + } + + for (uint32_t funcExportIndex : funcExportIndices) { + const FuncExport& fe = funcExports[funcExportIndex]; + const FuncType& funcType = metadata.getFuncExportType(fe); + + DebugOnly<CodeRange> cr = segment->codeRanges()[interpRangeIndex]; + MOZ_ASSERT(cr.value.isInterpEntry()); + MOZ_ASSERT(cr.value.funcIndex() == fe.funcIndex()); + + LazyFuncExport lazyExport(fe.funcIndex(), *stubSegmentIndex, + interpRangeIndex); + + size_t exportIndex; + const uint32_t targetFunctionIndex = fe.funcIndex(); + MOZ_ALWAYS_FALSE(BinarySearchIf( + exports_, 0, exports_.length(), + [targetFunctionIndex](const LazyFuncExport& funcExport) { + return targetFunctionIndex - funcExport.funcIndex; + }, + &exportIndex)); + MOZ_ALWAYS_TRUE( + exports_.insert(exports_.begin() + exportIndex, std::move(lazyExport))); + + // Exports that don't support a jit entry get only the interp entry. + interpRangeIndex += (funcType.canHaveJitEntry() ? 2 : 1); + } + + return true; +} + +bool LazyStubTier::createOneEntryStub(uint32_t funcExportIndex, + const Metadata& metadata, + const CodeTier& codeTier) { + Uint32Vector funcExportIndexes; + if (!funcExportIndexes.append(funcExportIndex)) { + return false; + } + + size_t stubSegmentIndex; + if (!createManyEntryStubs(funcExportIndexes, metadata, codeTier, + &stubSegmentIndex)) { + return false; + } + + const UniqueLazyStubSegment& segment = stubSegments_[stubSegmentIndex]; + const CodeRangeVector& codeRanges = segment->codeRanges(); + + const FuncExport& fe = codeTier.metadata().funcExports[funcExportIndex]; + const FuncType& funcType = metadata.getFuncExportType(fe); + + // Exports that don't support a jit entry get only the interp entry. + if (!funcType.canHaveJitEntry()) { + MOZ_ASSERT(codeRanges.length() >= 1); + MOZ_ASSERT(codeRanges.back().isInterpEntry()); + return true; + } + + MOZ_ASSERT(codeRanges.length() >= 2); + MOZ_ASSERT(codeRanges[codeRanges.length() - 2].isInterpEntry()); + + const CodeRange& cr = codeRanges[codeRanges.length() - 1]; + MOZ_ASSERT(cr.isJitEntry()); + + codeTier.code().setJitEntry(cr.funcIndex(), segment->base() + cr.begin()); + return true; +} + +bool LazyStubTier::createTier2(const Uint32Vector& funcExportIndices, + const Metadata& metadata, + const CodeTier& codeTier, + Maybe<size_t>* outStubSegmentIndex) { + if (!funcExportIndices.length()) { + return true; + } + + size_t stubSegmentIndex; + if (!createManyEntryStubs(funcExportIndices, metadata, codeTier, + &stubSegmentIndex)) { + return false; + } + + outStubSegmentIndex->emplace(stubSegmentIndex); + return true; +} + +void LazyStubTier::setJitEntries(const Maybe<size_t>& stubSegmentIndex, + const Code& code) { + if (!stubSegmentIndex) { + return; + } + const UniqueLazyStubSegment& segment = stubSegments_[*stubSegmentIndex]; + for (const CodeRange& cr : segment->codeRanges()) { + if (!cr.isJitEntry()) { + continue; + } + code.setJitEntry(cr.funcIndex(), segment->base() + cr.begin()); + } +} + +bool LazyStubTier::hasEntryStub(uint32_t funcIndex) const { + size_t match; + return BinarySearchIf( + exports_, 0, exports_.length(), + [funcIndex](const LazyFuncExport& funcExport) { + return funcIndex - funcExport.funcIndex; + }, + &match); +} + +void* LazyStubTier::lookupInterpEntry(uint32_t funcIndex) const { + size_t match; + if (!BinarySearchIf( + exports_, 0, exports_.length(), + [funcIndex](const LazyFuncExport& funcExport) { + return funcIndex - funcExport.funcIndex; + }, + &match)) { + return nullptr; + } + const LazyFuncExport& fe = exports_[match]; + const LazyStubSegment& stub = *stubSegments_[fe.lazyStubSegmentIndex]; + return stub.base() + stub.codeRanges()[fe.funcCodeRangeIndex].begin(); +} + +void LazyStubTier::addSizeOfMisc(MallocSizeOf mallocSizeOf, size_t* code, + size_t* data) const { + *data += sizeof(*this); + *data += exports_.sizeOfExcludingThis(mallocSizeOf); + for (const UniqueLazyStubSegment& stub : stubSegments_) { + stub->addSizeOfMisc(mallocSizeOf, code, data); + } +} + +size_t Metadata::sizeOfExcludingThis(MallocSizeOf mallocSizeOf) const { + return types->sizeOfExcludingThis(mallocSizeOf) + + globals.sizeOfExcludingThis(mallocSizeOf) + + tables.sizeOfExcludingThis(mallocSizeOf) + + tags.sizeOfExcludingThis(mallocSizeOf) + + funcNames.sizeOfExcludingThis(mallocSizeOf) + + filename.sizeOfExcludingThis(mallocSizeOf) + + sourceMapURL.sizeOfExcludingThis(mallocSizeOf); +} + +struct ProjectFuncIndex { + const FuncExportVector& funcExports; + explicit ProjectFuncIndex(const FuncExportVector& funcExports) + : funcExports(funcExports) {} + uint32_t operator[](size_t index) const { + return funcExports[index].funcIndex(); + } +}; + +FuncExport& MetadataTier::lookupFuncExport( + uint32_t funcIndex, size_t* funcExportIndex /* = nullptr */) { + size_t match; + if (!BinarySearch(ProjectFuncIndex(funcExports), 0, funcExports.length(), + funcIndex, &match)) { + MOZ_CRASH("missing function export"); + } + if (funcExportIndex) { + *funcExportIndex = match; + } + return funcExports[match]; +} + +const FuncExport& MetadataTier::lookupFuncExport( + uint32_t funcIndex, size_t* funcExportIndex) const { + return const_cast<MetadataTier*>(this)->lookupFuncExport(funcIndex, + funcExportIndex); +} + +static bool AppendName(const Bytes& namePayload, const Name& name, + UTF8Bytes* bytes) { + MOZ_RELEASE_ASSERT(name.offsetInNamePayload <= namePayload.length()); + MOZ_RELEASE_ASSERT(name.length <= + namePayload.length() - name.offsetInNamePayload); + return bytes->append( + (const char*)namePayload.begin() + name.offsetInNamePayload, name.length); +} + +static bool AppendFunctionIndexName(uint32_t funcIndex, UTF8Bytes* bytes) { + const char beforeFuncIndex[] = "wasm-function["; + const char afterFuncIndex[] = "]"; + + Int32ToCStringBuf cbuf; + size_t funcIndexStrLen; + const char* funcIndexStr = + Uint32ToCString(&cbuf, funcIndex, &funcIndexStrLen); + MOZ_ASSERT(funcIndexStr); + + return bytes->append(beforeFuncIndex, strlen(beforeFuncIndex)) && + bytes->append(funcIndexStr, funcIndexStrLen) && + bytes->append(afterFuncIndex, strlen(afterFuncIndex)); +} + +bool Metadata::getFuncName(NameContext ctx, uint32_t funcIndex, + UTF8Bytes* name) const { + if (moduleName && moduleName->length != 0) { + if (!AppendName(namePayload->bytes, *moduleName, name)) { + return false; + } + if (!name->append('.')) { + return false; + } + } + + if (funcIndex < funcNames.length() && funcNames[funcIndex].length != 0) { + return AppendName(namePayload->bytes, funcNames[funcIndex], name); + } + + if (ctx == NameContext::BeforeLocation) { + return true; + } + + return AppendFunctionIndexName(funcIndex, name); +} + +bool CodeTier::initialize(const Code& code, const LinkData& linkData, + const Metadata& metadata) { + MOZ_ASSERT(!initialized()); + code_ = &code; + + MOZ_ASSERT(lazyStubs_.readLock()->entryStubsEmpty()); + + // See comments in CodeSegment::initialize() for why this must be last. + if (!segment_->initialize(*this, linkData, metadata, *metadata_)) { + return false; + } + + MOZ_ASSERT(initialized()); + return true; +} + +void CodeTier::addSizeOfMisc(MallocSizeOf mallocSizeOf, size_t* code, + size_t* data) const { + segment_->addSizeOfMisc(mallocSizeOf, code, data); + lazyStubs_.readLock()->addSizeOfMisc(mallocSizeOf, code, data); + *data += metadata_->sizeOfExcludingThis(mallocSizeOf); +} + +const CodeRange* CodeTier::lookupRange(const void* pc) const { + CodeRange::OffsetInCode target((uint8_t*)pc - segment_->base()); + return LookupInSorted(metadata_->codeRanges, target); +} + +const wasm::TryNote* CodeTier::lookupTryNote(const void* pc) const { + size_t target = (uint8_t*)pc - segment_->base(); + const TryNoteVector& tryNotes = metadata_->tryNotes; + + // We find the first hit (there may be multiple) to obtain the innermost + // handler, which is why we cannot binary search here. + for (const auto& tryNote : tryNotes) { + if (tryNote.offsetWithinTryBody(target)) { + return &tryNote; + } + } + + return nullptr; +} + +bool JumpTables::init(CompileMode mode, const ModuleSegment& ms, + const CodeRangeVector& codeRanges) { + static_assert(JSScript::offsetOfJitCodeRaw() == 0, + "wasm fast jit entry is at (void*) jit[funcIndex]"); + + mode_ = mode; + + size_t numFuncs = 0; + for (const CodeRange& cr : codeRanges) { + if (cr.isFunction()) { + numFuncs++; + } + } + + numFuncs_ = numFuncs; + + if (mode_ == CompileMode::Tier1) { + tiering_ = TablePointer(js_pod_calloc<void*>(numFuncs)); + if (!tiering_) { + return false; + } + } + + // The number of jit entries is overestimated, but it is simpler when + // filling/looking up the jit entries and safe (worst case we'll crash + // because of a null deref when trying to call the jit entry of an + // unexported function). + jit_ = TablePointer(js_pod_calloc<void*>(numFuncs)); + if (!jit_) { + return false; + } + + uint8_t* codeBase = ms.base(); + for (const CodeRange& cr : codeRanges) { + if (cr.isFunction()) { + setTieringEntry(cr.funcIndex(), codeBase + cr.funcTierEntry()); + } else if (cr.isJitEntry()) { + setJitEntry(cr.funcIndex(), codeBase + cr.begin()); + } + } + return true; +} + +Code::Code(UniqueCodeTier tier1, const Metadata& metadata, + JumpTables&& maybeJumpTables) + : tier1_(std::move(tier1)), + metadata_(&metadata), + profilingLabels_(mutexid::WasmCodeProfilingLabels, + CacheableCharsVector()), + jumpTables_(std::move(maybeJumpTables)) {} + +bool Code::initialize(const LinkData& linkData) { + MOZ_ASSERT(!initialized()); + + if (!tier1_->initialize(*this, linkData, *metadata_)) { + return false; + } + + MOZ_ASSERT(initialized()); + return true; +} + +bool Code::setAndBorrowTier2(UniqueCodeTier tier2, const LinkData& linkData, + const CodeTier** borrowedTier) const { + MOZ_RELEASE_ASSERT(!hasTier2()); + MOZ_RELEASE_ASSERT(tier2->tier() == Tier::Optimized && + tier1_->tier() == Tier::Baseline); + + if (!tier2->initialize(*this, linkData, *metadata_)) { + return false; + } + + tier2_ = std::move(tier2); + *borrowedTier = &*tier2_; + + return true; +} + +void Code::commitTier2() const { + MOZ_RELEASE_ASSERT(!hasTier2()); + hasTier2_ = true; + MOZ_ASSERT(hasTier2()); + + // To maintain the invariant that tier2_ is never read without the tier having + // been committed, this checks tier2_ here instead of before setting hasTier2_ + // (as would be natural). See comment in WasmCode.h. + MOZ_RELEASE_ASSERT(tier2_.get()); +} + +uint32_t Code::getFuncIndex(JSFunction* fun) const { + MOZ_ASSERT(fun->isWasm() || fun->isAsmJSNative()); + if (!fun->isWasmWithJitEntry()) { + return fun->wasmFuncIndex(); + } + return jumpTables_.funcIndexFromJitEntry(fun->wasmJitEntry()); +} + +Tiers Code::tiers() const { + if (hasTier2()) { + return Tiers(tier1_->tier(), tier2_->tier()); + } + return Tiers(tier1_->tier()); +} + +bool Code::hasTier(Tier t) const { + if (hasTier2() && tier2_->tier() == t) { + return true; + } + return tier1_->tier() == t; +} + +Tier Code::stableTier() const { return tier1_->tier(); } + +Tier Code::bestTier() const { + if (hasTier2()) { + return tier2_->tier(); + } + return tier1_->tier(); +} + +const CodeTier& Code::codeTier(Tier tier) const { + switch (tier) { + case Tier::Baseline: + if (tier1_->tier() == Tier::Baseline) { + MOZ_ASSERT(tier1_->initialized()); + return *tier1_; + } + MOZ_CRASH("No code segment at this tier"); + case Tier::Optimized: + if (tier1_->tier() == Tier::Optimized) { + MOZ_ASSERT(tier1_->initialized()); + return *tier1_; + } + // It is incorrect to ask for the optimized tier without there being such + // a tier and the tier having been committed. The guard here could + // instead be `if (hasTier2()) ... ` but codeTier(t) should not be called + // in contexts where that test is necessary. + MOZ_RELEASE_ASSERT(hasTier2()); + MOZ_ASSERT(tier2_->initialized()); + return *tier2_; + } + MOZ_CRASH(); +} + +bool Code::containsCodePC(const void* pc) const { + for (Tier t : tiers()) { + const ModuleSegment& ms = segment(t); + if (ms.containsCodePC(pc)) { + return true; + } + } + return false; +} + +struct CallSiteRetAddrOffset { + const CallSiteVector& callSites; + explicit CallSiteRetAddrOffset(const CallSiteVector& callSites) + : callSites(callSites) {} + uint32_t operator[](size_t index) const { + return callSites[index].returnAddressOffset(); + } +}; + +const CallSite* Code::lookupCallSite(void* returnAddress) const { + for (Tier t : tiers()) { + uint32_t target = ((uint8_t*)returnAddress) - segment(t).base(); + size_t lowerBound = 0; + size_t upperBound = metadata(t).callSites.length(); + + size_t match; + if (BinarySearch(CallSiteRetAddrOffset(metadata(t).callSites), lowerBound, + upperBound, target, &match)) { + return &metadata(t).callSites[match]; + } + } + + return nullptr; +} + +const CodeRange* Code::lookupFuncRange(void* pc) const { + for (Tier t : tiers()) { + const CodeRange* result = codeTier(t).lookupRange(pc); + if (result && result->isFunction()) { + return result; + } + } + return nullptr; +} + +const StackMap* Code::lookupStackMap(uint8_t* nextPC) const { + for (Tier t : tiers()) { + const StackMap* result = metadata(t).stackMaps.findMap(nextPC); + if (result) { + return result; + } + } + return nullptr; +} + +const wasm::TryNote* Code::lookupTryNote(void* pc, Tier* tier) const { + for (Tier t : tiers()) { + const TryNote* result = codeTier(t).lookupTryNote(pc); + if (result) { + *tier = t; + return result; + } + } + return nullptr; +} + +struct TrapSitePCOffset { + const TrapSiteVector& trapSites; + explicit TrapSitePCOffset(const TrapSiteVector& trapSites) + : trapSites(trapSites) {} + uint32_t operator[](size_t index) const { return trapSites[index].pcOffset; } +}; + +bool Code::lookupTrap(void* pc, Trap* trapOut, BytecodeOffset* bytecode) const { + for (Tier t : tiers()) { + uint32_t target = ((uint8_t*)pc) - segment(t).base(); + const TrapSiteVectorArray& trapSitesArray = metadata(t).trapSites; + for (Trap trap : MakeEnumeratedRange(Trap::Limit)) { + const TrapSiteVector& trapSites = trapSitesArray[trap]; + + size_t upperBound = trapSites.length(); + size_t match; + if (BinarySearch(TrapSitePCOffset(trapSites), 0, upperBound, target, + &match)) { + MOZ_ASSERT(segment(t).containsCodePC(pc)); + *trapOut = trap; + *bytecode = trapSites[match].bytecode; + return true; + } + } + } + + return false; +} + +// When enabled, generate profiling labels for every name in funcNames_ that is +// the name of some Function CodeRange. This involves malloc() so do it now +// since, once we start sampling, we'll be in a signal-handing context where we +// cannot malloc. +void Code::ensureProfilingLabels(bool profilingEnabled) const { + auto labels = profilingLabels_.lock(); + + if (!profilingEnabled) { + labels->clear(); + return; + } + + if (!labels->empty()) { + return; + } + + // Any tier will do, we only need tier-invariant data that are incidentally + // stored with the code ranges. + + for (const CodeRange& codeRange : metadata(stableTier()).codeRanges) { + if (!codeRange.isFunction()) { + continue; + } + + Int32ToCStringBuf cbuf; + size_t bytecodeStrLen; + const char* bytecodeStr = + Uint32ToCString(&cbuf, codeRange.funcLineOrBytecode(), &bytecodeStrLen); + MOZ_ASSERT(bytecodeStr); + + UTF8Bytes name; + if (!metadata().getFuncNameStandalone(codeRange.funcIndex(), &name)) { + return; + } + if (!name.append(" (", 2)) { + return; + } + + if (const char* filename = metadata().filename.get()) { + if (!name.append(filename, strlen(filename))) { + return; + } + } else { + if (!name.append('?')) { + return; + } + } + + if (!name.append(':') || !name.append(bytecodeStr, bytecodeStrLen) || + !name.append(")\0", 2)) { + return; + } + + UniqueChars label(name.extractOrCopyRawBuffer()); + if (!label) { + return; + } + + if (codeRange.funcIndex() >= labels->length()) { + if (!labels->resize(codeRange.funcIndex() + 1)) { + return; + } + } + + ((CacheableCharsVector&)labels)[codeRange.funcIndex()] = std::move(label); + } +} + +const char* Code::profilingLabel(uint32_t funcIndex) const { + auto labels = profilingLabels_.lock(); + + if (funcIndex >= labels->length() || + !((CacheableCharsVector&)labels)[funcIndex]) { + return "?"; + } + return ((CacheableCharsVector&)labels)[funcIndex].get(); +} + +void Code::addSizeOfMiscIfNotSeen(MallocSizeOf mallocSizeOf, + Metadata::SeenSet* seenMetadata, + Code::SeenSet* seenCode, size_t* code, + size_t* data) const { + auto p = seenCode->lookupForAdd(this); + if (p) { + return; + } + bool ok = seenCode->add(p, this); + (void)ok; // oh well + + *data += mallocSizeOf(this) + + metadata().sizeOfIncludingThisIfNotSeen(mallocSizeOf, seenMetadata) + + profilingLabels_.lock()->sizeOfExcludingThis(mallocSizeOf) + + jumpTables_.sizeOfMiscExcludingThis(); + + for (auto t : tiers()) { + codeTier(t).addSizeOfMisc(mallocSizeOf, code, data); + } +} + +void Code::disassemble(JSContext* cx, Tier tier, int kindSelection, + PrintCallback printString) const { + const MetadataTier& metadataTier = metadata(tier); + const CodeTier& codeTier = this->codeTier(tier); + const ModuleSegment& segment = codeTier.segment(); + + for (const CodeRange& range : metadataTier.codeRanges) { + if (kindSelection & (1 << range.kind())) { + MOZ_ASSERT(range.begin() < segment.length()); + MOZ_ASSERT(range.end() < segment.length()); + + const char* kind; + char kindbuf[128]; + switch (range.kind()) { + case CodeRange::Function: + kind = "Function"; + break; + case CodeRange::InterpEntry: + kind = "InterpEntry"; + break; + case CodeRange::JitEntry: + kind = "JitEntry"; + break; + case CodeRange::ImportInterpExit: + kind = "ImportInterpExit"; + break; + case CodeRange::ImportJitExit: + kind = "ImportJitExit"; + break; + default: + SprintfLiteral(kindbuf, "CodeRange::Kind(%d)", range.kind()); + kind = kindbuf; + break; + } + const char* separator = + "\n--------------------------------------------------\n"; + // The buffer is quite large in order to accomodate mangled C++ names; + // lengths over 3500 have been observed in the wild. + char buf[4096]; + if (range.hasFuncIndex()) { + const char* funcName = "(unknown)"; + UTF8Bytes namebuf; + if (metadata().getFuncNameStandalone(range.funcIndex(), &namebuf) && + namebuf.append('\0')) { + funcName = namebuf.begin(); + } + SprintfLiteral(buf, "%sKind = %s, index = %d, name = %s:\n", separator, + kind, range.funcIndex(), funcName); + } else { + SprintfLiteral(buf, "%sKind = %s\n", separator, kind); + } + printString(buf); + + uint8_t* theCode = segment.base() + range.begin(); + jit::Disassemble(theCode, range.end() - range.begin(), printString); + } + } +} + +void wasm::PatchDebugSymbolicAccesses(uint8_t* codeBase, MacroAssembler& masm) { +#ifdef WASM_CODEGEN_DEBUG + for (auto& access : masm.symbolicAccesses()) { + switch (access.target) { + case SymbolicAddress::PrintI32: + case SymbolicAddress::PrintPtr: + case SymbolicAddress::PrintF32: + case SymbolicAddress::PrintF64: + case SymbolicAddress::PrintText: + break; + default: + MOZ_CRASH("unexpected symbol in PatchDebugSymbolicAccesses"); + } + ABIFunctionType abiType; + void* target = AddressOf(access.target, &abiType); + uint8_t* patchAt = codeBase + access.patchAt.offset(); + Assembler::PatchDataWithValueCheck(CodeLocationLabel(patchAt), + PatchedImmPtr(target), + PatchedImmPtr((void*)-1)); + } +#else + MOZ_ASSERT(masm.symbolicAccesses().empty()); +#endif +} |